void EnqueueAndDispatch()

in src/Microsoft.Azure.Relay/Common/InputQueue.cs [378:451]
68 lines of code
11 McCabe index (conditional complexity)

        void EnqueueAndDispatch(Item item, bool canDispatchOnThisThread)
        {
            bool disposeItem = false;
            IQueueReader reader = null;
            bool dispatchLater = false;
            IQueueWaiter[] waiters;
            bool itemAvailable;

            lock (ThisLock)
            {
                itemAvailable = !((queueState == QueueState.Closed) || (queueState == QueueState.Shutdown));
                this.GetWaiters(out waiters);

                if (queueState == QueueState.Open)
                {
                    if (canDispatchOnThisThread)
                    {
                        if (readerQueue.Count == 0)
                        {
                            itemQueue.EnqueueAvailableItem(item);
                        }
                        else
                        {
                            reader = readerQueue.Dequeue();
                        }
                    }
                    else
                    {
                        if (readerQueue.Count == 0)
                        {
                            itemQueue.EnqueueAvailableItem(item);
                        }
                        else
                        {
                            itemQueue.EnqueuePendingItem(item);
                            dispatchLater = true;
                        }
                    }
                }
                else
                {
                    // queueState == QueueState.Closed || queueState == QueueState.Shutdown
                    disposeItem = true;
                }
            }

            if (waiters != null)
            {
                if (canDispatchOnThisThread)
                {
                    CompleteWaiters(itemAvailable, waiters);
                }
                else
                {
                    CompleteWaitersLater(itemAvailable, waiters);
                }
            }

            if (reader != null)
            {
                InvokeDequeuedCallback(item.DequeuedCallback);
                reader.Set(item);
            }

            if (dispatchLater)
            {
                ActionItem.Schedule(s => OnDispatchCallback(s), this);
            }
            else if (disposeItem)
            {
                InvokeDequeuedCallback(item.DequeuedCallback);
                DisposeItem(item);
            }
        }